Air-cooled canned motor pumps designed for hightemperature applications isolate liquid in the motor section of the unit for the hot process fluid in the pump casing with a series of pressure ports located in the front bearing housing or pump casing adapter. This isolated liquid (usually the same fluid as the pumped fluid) is circulated through an air-cooled heat exchanger by an auxiliary impeller located on the rotor assembly.
This design allows the motor and bearing environment to be at a much lower temperature than the process fluid, enabling the use of standard bearings and motor insulation significantly reducing both first and long term operating and maintenance costs and eliminates the need for cooling water that could be of poor quality.